Holder/impactor for contoured bone plate for fracture fixation

ABSTRACT

A bone fixation plate for fixation of fractures having a small terminal bone fragment, such as fractures of the distal radius. The plate includes an elongated body, and two hook members extending from a first end of the elongated body. A contoured region is configured to approximate the surface contour of the distal radius proximate the volar rim, the dorsal rim, or the radial arm. Each hook member is configured to provide subchondral support to a distal bone fragment, without causing shortening of the fragment into the metaphyseal bone, and without providing a bending torque directed to the base of the plate. The tooth members of the hook plate are preferably sharpened at their tips and edges to facilitate their impaction. A holder/impactor for gripping the radial hook plate, and for further facilitating impacting of the hook plate without the need to pre-drill pilot holes, is also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of pending U.S. patentapplication Ser. No. 13/103,658, filed May 9, 2011, the entirety ofwhich is hereby incorporated by reference, which is a division of U.S.patent application Ser. No. 12/114,916 filed May 5, 2008, now U.S. Pat.No. 8,177,822, the entirety of which is hereby incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, in general, to the fixation of bonefractures and, more particularly, to the fixation of bone fractureshaving small fragments proximate a terminal end of a bone.

2. Description of Related Art

Plates and screws are well accepted techniques for fixation offractures. The standard bone plate is a planar bar of material, usuallymetal, having circular and/or slotted holes through which bone screwsare placed. The bone plate is used to span a fracture and fixationscrews are placed through holes in the bone plate positioned on eitherside of the fracture to secure the bone fragments the plate.

One variation of the standard bone plate is to modify the configurationof the screw holes to help provide compression across the fracture asthe screw is placed. Another variation is to include female threadswithin the perimeter of the bone plate's screw holes, engaging malethreads on the head of the screw to lock the screw to the plate.

Difficulties in using bone plates may arise in certain fracturesoccurring relatively close to the end of a bone, creating a relativelysmall end fragment. In this situation, there may simply be not enoughbone available in the end fragment to accommodate a sufficient number ofscrews to achieve secure fixation. As a result, a surgeon using aconventional bone plate may use a suboptimal number of screws, which canlead to postoperative failure.

One example of a fracture occurring relatively close to the end of abone is a fracture of the lateral malleolus, the terminal portion of thefibula that is present on the outside of the ankle, occurring close toits tip. In such situations, only a very small distal fragment may bepresent, providing inadequate room for more than one or two screws to beplaced. Moreover, since the deep portion of this bone is a part of theoverall ankle joint, screws cannot be placed through both cortices, asis commonly practice with plate/screw techniques. Accordingly, thesurgeon may be faced with the undesirable situation of having thepatient leave the operating room with only one or two screws engaging abone surface directly under a bone plate.

In the past, one technique surgeons have used in an attempt to provideenhanced fixation or grip of a small terminal bone fragment is to beginwith a standard plate and cut the plate transversely across at its lastscrew hole. Using a pair of surgical pliers or other suitableinstrument, the remaining bone plate material on opposing sides of thepartially remaining hole is bent around the outer surface of theterminal bone fragment. To some degree, this helps supplement thetenuous fixation provided by only one or two screws in the smallterminal fragment. However, this terminal bone fragment may still remainfar from being well secured.

In another previous technique disclosed in “Use of Zuelzer Hook Plate inthe Treatment of Olecranon Fractures” by Wesely, Barenfeld, andEisenstein, The Journal of Bone & Joint Surgery, Volume 58-A, Issue No6, September 1976, pages 859-863, a further modification of thistechnique is described in which a flat plate is pre-contoured with twohooks at one end. The hooks are bent so that they are parallel to thelongitudinal axis of the flat plate. The plate is applied to a fracturedbone such as the olecranon by manually pressing the hooks into the boneand fixing the plate to the bone surface with screws. Although thistechnique adds the theoretical advantage of penetration of the terminalfragment with the hooks, if this plate is applied to an anatomic site inwhich the bone flares out at the terminal end, since the hooks areparallel to the linear axis of the plate, as the hooks are impacted, theplate will not sit flush with the bone surface past the flare at theterminal end but rather come to lie in a position that sits off thebone. In addition, this technique does not address the problem ofcreating holes in the bone at the correct depth for engagement by thehooks, but rather relies on manual pressure on the plate to attemptpenetration of the bone by the hooks at whatever level they happen tocontact. As can be noted by the examples in this article, the hooks mayfail to penetrate the bone resulting in less than satisfactoryengagement and fixation of the terminal fragment by the hooks as well asprominence of the hooks in the soft tissue because of incompleteseating. Finally, since these implants have hooks that extend an equaldistance from the end of the plate, this design does not allowcompletely seating of both hooks in the common situation in which thebone surface at the terminal end is at an angle to the plane that isperpendicular to the long axis of the bone.

Distal radius fractures (what is often meant when using the term ‘wristfracture’) are common injuries. These fractures are often comminuted andunstable. It is of importance in addressing such fractures to restore asmooth, anatomic and congruent articular surface with enough stabilityso that it does not displace during healing. In other locations in thebody one objective of internal fixation is to produce compressionbetween stable and unstable fragments in order to promote healing.However, in the case of the distal radius fractures, fixation that wouldproduce this type of compressive loads between the articular fragmentsand the shaft may result in migration of the fragments, loss of length,malunions and failure. For this reason, the tenets of internal fixationfor distal radius fractures are different, aimed at achieving a stableanatomic reduction while maintaining the joint surface in spacesupported out to length.

Recently, surgical fixation has become the procedure of choice for manyof these unstable distal radius fractures. One common method of fixationis to apply a plate to the volar surface of the radius, with a lockedfixed angle support behind the bone under the articular surface. As loadis applied to the end of the bone during healing, the fixed struts underthe articular surface prevent setting of the articular surface into thesoft bone at the end of the radius and loss of fracture reduction andlength.

An early design that used this approach was the SCS plate, manufacturedby Small Bone Innovations, Inc. This plate has four tines that areintegrally formed with the plate and bent at a right angle to the planeof the predominant distal surface of the plate. These tines functionedas fixed posts. However, there are certain shortcomings to this design.First, since there are four posts integrally formed with the plate, asomewhat cumbersome drill guide apparatus is required to be applied tothe bone in order to drill the holes for all four posts simultaneously.This requires that the surgeon reduce the fracture (restore allfragments in space to a position that reflected normal anatomy of thebone) and then maintain it in position while the drill guide wasapplied, then removed, and the plate then applied. This can besignificantly difficult to achieve. Another shortcoming that arises fromthe use of four fixed posts is that the drill guide cannot generally bemoved during the drilling of each of the four holes. In addition, thesurgeon is required to simultaneously align each of the four drilledholes with the corresponding leading tips of each of the four tines inorder to get the plate inserted. Since this plate was intended to be asingle size approach to variable fracture patterns, fracture elementsdidn't always line up in the optimal position for insertion of thetines. In other words, this design lacks the flexibility often requiredto avoid placing tines directly through fracture lines (which can pushfragments apart, contributing to instability). These issues can lead toinadequate fixation.

A variation of the foregoing technique replaces the tines with pegs orscrews, insertable at fixed angles through the body of the plate. Thisdesign has the advantage of allowing a surgeon to apply the plate andindividually drill each hole and insert each peg separately, thusavoiding the difficulties associated with inserting four tines intodrilled pilot holes simultaneously. However, this design still remains aone size fits all solution, and lacks flexibility to line up fixationfor some complex fracture patterns. In addition, this design stillrequires that the anatomy be restored along the articular surface andheld in place in order to apply the plate.

Another variation of this design is a plate that has fixation pegs thatcan be directed at a variety of angles, and then angularly locked intothe plate. One example is the Volar Bearing Plate, manufactured byTriMed, Inc. Although this approach adds further flexibility to thedirection of the fixation pegs, it still requires the surgeon to restoreand hold the anatomy while the fixation is taking place, which cansometimes be difficult to perform. In addition, this design does notsolve the problem of avoiding the placement of pegs through fracturelines, since the relative position of the peg holes is fixed, and movingthe entry of one peg by shifting the plate to a different locationresults in corresponding movement of the placement locations of all ofthe other associated pegs.

Generally volar fixation plates need to be thick in cross-section inorder to provide sufficient material to allow enough internal threads inthe holes in order to securely lock the cooperatively threaded peg tothe plate (whether at a fixed or variable angle). Since it is known thatthick implants close to the rim of the distal radius may often causeirritation and even rupture of important tendons and other vitalstructures nearby, existing volar generally plates do not extend to thedistal rim. As a result, small fractures of the distal volar rim areoften not be secured by these plate designs, which can result in thefragment flipping over the edge of the plate, potentially causingcatastrophic loss of reduction and dislocation of the carpal bones ofthe wrist.

Another approach to fixation of complex fractures uses a fragmentspecific technique. Generally, this method consists of individuallysecuring each fragment separately with a specific implant. This canovercome the requirement that the surgeon hold the entire reduction inplace, since each fragment can be reduced and fixed one at a time. Onecommon implant used for this technique utilizes small plates with smallfixed angle pegs, screws, or pins for purchase of the unstable fragment.These implants require the fragment to be reduced, the plate applied,and then the holes prepared and drilled followed by insertion andlocking of the pegs, screws, or pins. These multiple steps can besomewhat difficult and time consuming, and may be an objection toapplication of this technique.

Another type of fragment specific implant uses wire forms or buttressingpins that penetrate fragments and hold it out to length. For example,the Volar Buttress Pin, manufactured by TriMed, Inc., is an implant thatcan be used to extend over the volar or dorsal rim. This implant is lowprofile and accordingly is unlikely to interfere with adjacent tendonsor other vital structures. The buttress pin penetrates the fragment forfixation. However the surgical technique for this type of implant doesrequire pre-drilling the holes for insertion of the legs of the buttresspin. These steps can be difficult to perform, often requiring surgeonswith above average ability and experience. In addition, since thesetypes of implants are a type of bent wire, they lack the strength andrigidity of larger plates.

Hook plates are implants that have been used at other locations toaddress fixation of a small terminal fragment with little availableosseous bone area to accommodate fixation screws. Although early designssuch as the LCP Hook Plate manufactured by Synthes, Inc. wrap around theend of the bone, these types of implants do not achieve any internalpurchase of the fragment to be secured, and may have very limited to nopurchase overall, resulting in poor rotational stability and limitedresistance to sideways drift of the terminal fragment.

The hook plates of the present invention, configured for application tothe lateral malleolus or the olecranon, achieve fixation of terminalfragments with two ‘teeth’ that provide rigid internal purchase of thefragment. These hook plates provide for rigid fixation of the terminalfragment and angular or translational movement under the plate. Inaddition, this type of plate promotes compressive load across thefracture which is intended for treatment at these locations.

For fixation of the distal radius, however, the configuration of thesetypes of hook plates is not optimal, especially for fractures involvingthe volar or dorsal rim. Since hook plates of the present inventionconfigured for application to the lateral malleolus or the olecranonpromote compression against the stable fragment, in the case of distalradius fixation this would cause shortening of the fragment into themetaphyseal bone, and thus loss of articular reduction. The use of suchhook plates is counterintuitive thus contraindicated for this type ofinternal fixation.

Accordingly, it is an object of the present invention to provide a boneplate that adequately secures a small bone fragment at a terminal end ofa bone.

It is a further object of the present invention to provide a bone platethat can be seated flush against a bone characterized by a flare at theterminal segment, yet sill providing full engagement of the smallterminal fragment by complete seating of one or more hooks into bone. Itis a further object of the present invention to provide a means tocreate pilot holes in the terminal fragment for engagement by the hooksin the plate such that the hook or hooks in the plate engage the bone atthe correct depth and trajectory so as to direct the plate to advanceboth longitudinally as well as drop down against the surface of the boneas it is seated.

It is another object of the present invention to provide a design thathas a contour that approximates the flare of the terminal segment of abone as well as provides one or more hooks that are angled along an axisthat approximates the best linear fit approximation of such flare.

It is another object of the present invention to provide an implant torigidly hold bone fragments proximate the volar rim, dorsal rim, orother area proximate to the articular surface of the distal radius, andto provide subchondral support of the articular surface to prevent lossof length.

It is another object of the present invention to provide an implant thatresists shortening of bone fragments and acts like a buttress to thedistal fragments.

It is another object of the present invention to provide an implant thatresists application of bending torque directed to the base of the plate.

It is another object of the present invention to provide an implant thatcan be impacted without the need to pre-drill pilot holes in the boneproximate the fracture site.

It is another object of the present invention to provide implants havingtines, or toothed members, positioned at various locations andindividualized to a specific pattern of an injury.

It is another object of the present invention to provide aholder/impactor to securely grip a bone plate to be implanted, and toprovide a striking surface to permit the surgeon to impact the tines ofthe bone plate directly into the distal radius.

It is another object of the present invention to provide a drill guidefacilitating accurate placement of a bone plate proximate a terminal endof a bone.

These and other objects and features of the present invention willbecome apparent in view of the present specification, drawing andclaims.

BRIEF SUMMARY OF THE INVENTION

The present invention comprises a bone plate for fixing fractures havinga small terminal fragment. The bone plate has an elongated body having afirst end, a second end, a top surface, a bottom surface, and an angledor curved flared region disposed between the first end and the secondend that can be described by a best fit first longitudinal axis. Atleast one hook member is provided proximate the first end and has aprong region having a second longitudinal axis. Moreover, the firstlongitudinal axis and the second longitudinal axis are substantiallyparallel to each other.

In one preferred embodiment of the present invention, the at least onehook member comprises a first hook member and a second hook member, witheach of the first and second hook members having a prong region with asecond longitudinal axis substantially parallel to the firstlongitudinal axis. The first hook member has a first curved regionincluding a first apex, the second curved member has a second curvedregion including a second apex, and the distance between the second endand the first apex is greater than the distance between the second endand the second apex. In another preferred embodiment, the distancebetween the second end and the first apex is equal to the distancebetween the second end and the second apex.

Moreover, in a preferred embodiment, the elongated body includes a firstregion and a second region on opposing sides of the angled region, withthe first region, angled region, and second region collectively form asurface substantially corresponding to the surface contour of the humanfibula at the lateral malleolus. Other embodiments contemplated by thepresent invention may be formed with the angled region designed toconform to the contour of other sites of application in which the bonesurface flares superficially at the terminal end, such as the olecranon,proximal ulna, proximal or distal humerus, medial malleolus, or similarbones. The elongated body preferably includes at least one bone screwaccepting hole extending therethrough, and at least a portion of thebottom surface of the elongated body has a concave curvature. Thisconcave curvature is dimensioned to substantially correspond to thesurface curvature of the human fibula proximate the lateral malleolus.Moreover, the at least one hook member has a curved region curving fromthe elongated body proximate the first end, back towards the second endof the elongated body and terminating in the prong region.

The present invention also comprises a multiple barreled drill guidefacilitating the drilling of at least two parallel holes at the distalend of a bone at the correct depth. The multiple barreled drill guidehas a body, at least two sleeves coupled to the body in substantiallyparallel orientation relative to each other, with each sleeve having afirst longitudinal axis, and an elongated positioning member extendingfrom the body and having a second longitudinal axis. The firstlongitudinal axis may be angled relative to the second longitudinal axissuch that, when the drill guide is positioned with the elongatedpositioning member disposed along a distal end of a human fibula and thesleeves abutting a terminal end of the fibula, the first longitudinalaxis of each sleeve extends into the lateral malleolus of the fibula. Ina preferred embodiment, this angle between the first longitudinal axisand the second longitudinal axis is approximately three degrees. Inanother preferred embodiment, the first longitudinal axis and secondlongitudinal axis are parallel.

The double barreled drill guide further includes a cooperating innerdrill guide configured to releasably engage the multiple barreled drillguide. The inner drill guide includes an inner drill guide body, and atleast two inner sleeves coupled to the inner drill guide body, with atleast a portion of each of the inner sleeves being aligned by the innerdrill guide body for axial insertion into at least a portion of acorresponding sleeve of the multiple barreled drill guide. In onevariation of the inner drill guide, at least one of the inner sleevesincludes an internal channel sized to accommodate a 0.9 mm Kirshnerwire, with an outer diameter of 2.0 mm to fit in the double barreledguide which can accept a 2.0 mm drill.

The double barreled drill guide further includes a gauge configured toreleasably engage the multiple barreled drill guide. The gauge has agauge body, a first elongated member coupled to the gauge body andhaving a first end, a second elongated member coupled to the gauge bodyand having a second end. At least a portion of the first and secondelongated members are aligned by the gauge body for axial insertion intoat least a portion of a corresponding sleeve of the multiple barreleddrill guide. Moreover, the first and second elongated members are ofunequal length. The gauge further includes indicia disposed on the gaugebody and indicating a current orientation of the gauge.

In other embodiments of the present invention, a hook plate isconfigured, upon implantation, to rigidly hold the volar or dorsal rimof the distal radius, and to provide subchondral support of thearticular surface to prevent loss of length. This is achieved byconfiguring the hook plate to have a bottom curvilinear surface thatcoincides with the flare and surface geometry of either the volar ordorsal surface of the distal radius, respectively, with the plateterminating in two hooks to penetrate the volar or dorsal rim along thesubchondral bone. These hooks do not angle back in line with the longaxis of the bone, as in the case of hook plates of the present inventionfor addressing fractures of the lateral malleolus, but rather anglealong the direction of the subchondral bone. These distal radius hookplaces are thus designed to resist shortening of the fragment and to actlike a buttress, or support, for the distal bone fragments. Unlike otherhook plates that are used to compress a fragment with bending torque onthe hooks directed away from the plate, these implants are used toresist shortening and need to resist a bending torque directed to thebase of the plate.

The radial hook plate in one embodiment uses hooks that are sharpened attheir tips and at their leading edges. This allows the hooks to besimultaneously impacted like a nail or staple, and eliminates the stepsof setting up a drill guide, drilling, removing the drill guide, findingthe holes with both hooks and impacting. Rather, the implant can simplybe applied and hammered into place. The surgeon simply applies the hooksin position, hammers the hooks along the subchondral surface, andapplies the plate proximally to the shaft, reducing the fragment. Sincethe distal fixation elements or tooth members do not require a threadedhole, the thickness of the implant can be significantly reduced, therebyreducing the likelihood of irritation of tendons and other soft tissues.A holder/impactor instrument is provided to facilitate implantation andthe precision of intended placement in the absence of pre-drilled pilotholes at the fracture site.

Moreover, depending upon the configuration of a particular fracture, thenumber and location of implants can be individualized to the specificpattern of the injury. For instance, two plates can be used side by sideto individually fix fragments along the ulnar side and the radial sideof the distal radius, including plates having left and right offsettines, or hook members, relative to a longitudinal axis of the hookplate. This allows the plate to be aligned with the long axis of thebone proximally where the bone is narrow, but still get the spread offixation over a wider area distally where the bone is wider. Moreover,volar and dorsal plates can be combined, or volar, dorsal, and radialarm plates may be employed in various combinations. In this way,fixation can be easily customized to variation in the position of thefracture lines.

In certain embodiments of the distal radius hook plates, a second tierof subchondral fixation is provided by adding a fixed angle peg holethat is directed at an angle that extends between the axes of the hooks.This allows a third point of subchondral support in addition to the twohooks, acting like a cup behind the articular surface.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a simplified anterior view of a portion of the human rightankle, showing fractures of both the lateral malleolus of the fibula andmedial malleolus of the tibia;

FIG. 2A is a perspective view of a 6-hole left offset fracture fixationplate of the present invention, configured for use in the fixation ofcertain fractures of the ankle;

FIG. 2B is a bottom view of the 6-hole left offset fracture fixationplate;

FIG. 2C is a right side view of the 6-hole left offset fracture fixationplate;

FIG. 2D is a top plan view of the 6-hole left offset fracture fixationplate;

FIG. 2E is a sectional view of the 6-hole left offset fracture fixationplate, taken generally along lines 2E-2E of FIG. 2D;

FIG. 2F is a front view of the 6-hole left offset fracture fixationplate;

FIG. 3A is a top plan view of a 10-hole right offset fracture fixationplate of the present invention, configured for use in the fixation ofcertain fractures of the ankle;

FIG. 3B is a bottom view of the 10-hole right offset fixation plate;

FIG. 4 is a perspective view of the double barreled drill guide of thepresent invention, shown positioned adjacent the lateral malleolus;

FIG. 5 is an exploded perspective view of the drill guide base assemblyand interchangeable drill guide insert;

FIG. 6 is an exploded perspective view of the drill guide base assembly;

FIG. 7A is a perspective view of the body portion of the drill guidebase assembly;

FIG. 7B is a back view of the body portion of the drill guide baseassembly;

FIG. 7C is a sectional view of the body portion of the drill guide baseassembly, taken generally along lines 7C-7C of FIG. 7B;

FIG. 8A is an exploded perspective view of the interchangeable guidewire insert;

FIG. 8B is a side view of the interchangeable guide wire insert;

FIG. 9A is an exploded left perspective view of the gauge assembly;

FIG. 9B is a left perspective view of the gauge assembly;

FIG. 9C is a top view of the gauge assembly;

FIG. 10 is an anterior view, looking posteriorly, of the left tibia andfibula and showing, in particular, a 6-hole fracture fixation platepositioned immediately prior to impacting the hook members andaffixation of the plate to the left fibula;

FIG. 11 is an anterior view of the right fibula showing, in particular,the positioning of the 6-hole fracture fixation plate followingimplantation and reduction of the fracture of the lateral malleolus inwhich the prong regions cross the fracture site; and

FIG. 12 is an anterior view of the right fibula showing, in particular,the positioning of the 6-hole fracture fixation plate followingimplantation and reduction of the fracture of the lateral malleolus inwhich the prong regions do not cross the fracture site.

FIG. 13A is top perspective view of a 4-hole, neutral offset fracturefixation plate of the present invention, configured for volarapplication in the fixation of certain fractures of the distal radius;

FIG. 13B is a bottom perspective view of the fracture fixation plate ofFIG. 13A;

FIG. 13C is a left side view of the fracture fixation plate of FIG. 13A;

FIG. 13D is a top plan view of the fracture fixation plate of FIG. 13A;

FIG. 13E is a bottom plan view of the fracture fixation plate of FIG.13A;

FIG. 14A is top perspective view of a 4-hole, left offset fracturefixation plate of the present invention, configured for volarapplication in the fixation of certain fractures of the distal radius;

FIG. 14B is a bottom perspective view of the fracture fixation plate ofFIG. 14A;

FIG. 14C is a top plan view of the fracture fixation plate of FIG. 14A;

FIG. 14D is a bottom plan view of the fracture fixation plate of FIG.14A;

FIG. 15A is top perspective view of a 4-hole, right offset fracturefixation plate of the present invention, configured for volarapplication in the fixation of certain fractures of the distal radius;

FIG. 15B is a bottom perspective view of the fracture fixation plate ofFIG. 15A;

FIG. 15C is a top plan view of the fracture fixation plate of FIG. 15A;

FIG. 15D is a bottom plan view of the fracture fixation plate of FIG.15A;

FIG. 16A is top perspective view of a 7-hole, neutral offset fracturefixation plate of the present invention, configured for volarapplication in the fixation of certain fractures of the distal radius;

FIG. 16B is a bottom perspective view of the fracture fixation plate ofFIG. 16A;

FIG. 16C is a left side view of the fracture fixation plate of FIG. 16A;

FIG. 17A is top perspective view of a 4-hole, neutral offset fracturefixation plate of the present invention, configured for dorsalapplication in the fixation of certain fractures of the distal radius;

FIG. 17B is a bottom perspective view of the fracture fixation plate ofFIG. 17A;

FIG. 17C is a left side view of the fracture fixation plate of FIG. 17A;

FIG. 17D is a top plan view of the fracture fixation plate of FIG. 17A;

FIG. 17E is a bottom plan view of the fracture fixation plate of FIG.17A;

FIG. 18 is a dorsal view, looking palmarly, of the left radius andshowing, in particular, the positioning of a 3-hole, 5-hole, or 7-hole,neutral offset fracture fixation plate of the present invention,configured for radial column application in the fixation for certainfractures of the distal radius, following implantation and reduction ofa fracture;

FIG. 19 is a medial view, looking laterally, of a fractured right radiusand showing, in particular, several fragments of the volar rim and thedorsal rim;

FIG. 20 is a top perspective view of the 4-hole, neutral offset fracturefixation plate of FIGS. 13A through 13E, shown impacted volarly into afractured distal radius and prior to final affixation;

FIG. 21 is a medial view, looking laterally, of the distal radius andshowing, in particular, a 4-hole, neutral offset fracture fixation plateof FIGS. 13A through 13E, configured for volar application and shownimpacted volarly into a fractured distal radius and prior to finalaffixation;

FIG. 22 is a top perspective view of the 4-hole, left offset fracturefixation plate of FIGS. 14A through 14D, as well as the 4-hole, rightoffset fracture fixation plate of FIGS. 15A through 15D, both shownimpacted volarly into a fractured distal radius and prior to finalaffixation;

FIG. 23 is a medial view, looking laterally, of the distal radius andshowing, in particular, a variation of the neutral offset fracturefixation plate of FIGS. 13A through 13E, configured for volarapplication with a locking peg and shown implanted for fixation of afractured distal volar radius;

FIG. 24A is a top view of the 7-hole, neutral offset fracture fixationplate, shown impacted dorsally into a fractured distal radius and priorto final affixation;

FIG. 24B is a left side view of the 7-hole, neutral offset fracturefixation plate of FIG. 24A, shown impacted dorsally into a fractureddistal radius and prior to final affixation;

FIG. 25 is a left side view of a holder/impactor for use with the distalradius fracture fixation plates of the present invention, shown securedto the 7-hole, volar neutral offset fracture fixation plate of FIGS. 16Athrough 16C;

FIG. 26 is a bottom perspective view of the holder/impactor of FIG. 25,shown secured to a fracture fixation plate;

FIG. 27 is a see-through view of a portion of the holder/impactor ofFIG. 25 and showing, in particular, the foot member in its fullyretracted position within the distal housing;

FIG. 28 is a top perspective view of the holder/impactor of FIG. 25,shown secured to a fracture fixation plate;

FIG. 29 is a front view of the holder/impactor of FIG. 25, shown securedto a fracture fixation plate;

FIG. 30 is a bottom plan view of a portion of the 7-hole, volar neutraloffset fracture fixation plate of FIGS. 16A through 16C, shown securedto the holder/impactor of FIG. 25;

FIG. 31 is a left side view of another holder/impactor for use with thedistal radius fracture fixation plates of the present invention, shownsecured to the 4-hole, volar neutral offset fracture fixation plate ofFIGS. 13A through 13E; and

FIG. 32 is a top cross-sectional view of a portion of the distalgripping region of the holder/impactor of FIG. 31, taken generally alonglines 32-32 of FIG. 31, shown secured to the 4-hole, volar neutraloffset fracture fixation plate of FIGS. 13A through 13E.

DETAILED DESCRIPTION OF THE INVENTION

While several different embodiments of the present invention aredescribed herein and shown in the various figures, common referencenumerals in the figures denote similar or analogous elements orstructure amongst the various embodiments.

A simplified anterior view of a portion of the right human ankle isshown in FIG. 1 as comprising fibula 10, tibia 20, and talus 30. Rightfibula 10 is shown having a fracture of the lateral malleolus 11thereof, creating a small terminal fragment 13 proximate fracture site12. Simultaneously, right tibia 20 is shown having a fracture of themedial malleolus 21 thereof, creating a small terminal fragment 23proximate fracture site 22.

A six-hole left offset bone plate 40 of the present invention,configured for use in conjunction with fractures of the lateralmalleolus, is shown in FIGS. 2A through 2F as comprising an elongatedbody 41, having a first end 42 proximate first hook member, or toothmember 44 and second hook member, or tooth member 45. Elongated body 41includes a first region 48 proximate first end 42, a second region 46proximate a second end 43, and an intermediate, angled, or “flared”region 47 disposed between first region 48 and second region 46.Elongated body 41 includes a plurality of apertures extendingtherethrough for use in conjunction with conventional bone screws,including five circular holes 66, and one slotted hole 67. As best seenin FIGS. 2B and 2D, circular holes 66 are in a collectively staggeredoff-center orientation, relative to a longitudinal axis of elongatedbody 41, while slotted hole 67 is centered along this longitudinal axis.Moreover, and as best seen in FIG. 2A, slotted hole 67 and each circularhole 66 includes an associated countersunk, beveled perimeter, relativeto the top surface of elongated body 41, facilitating the frusto-conicalheads of conventional bone screws to be fully seated against, and hencein securing engagement with, an associated hole upon implantation.

As best seen in FIG. 2C, angled region 47 is generally defined andcreated by the presence of first radius of curvature 52 relative to thebottom surface of bone plate 40 proximate the juncture of substantiallylinear first region 48 and substantially linear angled region 47;together with the presence of second radius of curvature 50 relative tothe top surface of bone plate 40 proximate the juncture of substantiallylinear second region 46 and angled region 47. The length of the linearangled region 47 and the inclination defined as the angle 49 between aline 63 parallel to linear angled region 47 with the longitudinal axisof the elongated body 41, substantially match the length and inclinationof the flare of the associated bone requiring fracture fixation. Itshould be noted that substantially linear first region 48 may in fact bea curved surface that may be approximated by a best fit inclinationangle 49. As a result, the bottom surface of elongated body 41 of boneplate 40 has an overall longitudinal contour which substantiallycorresponds to the flared profile of the distal end of the human fibulaproximate the lateral malleolus. These values, including the lengths ofangled region 47, first region 48, and second region 46, radii ofcurvature 50 and 52, and angles 49 and 69, may be modified during themanufacturing process to create a hooked bone plate specificallytailored for other sites of application having a bone surface flaresuperficially proximate the terminal end, such as the medial malleolus,olecranon, proximal ulna, proximal femur, proximal fifth metatarsal,proximal or distal humerus, or other such sites of application.

In one preferred embodiment, the length, contour and relative angling oflinear angled region 47, relative to first region 48 and second region46, is designed and to match the flare of the surface contour of thesite of application using an electronically scanned or mathematicalthree-dimensional model of the site of application, such as the lateralmalleolus or olecranon as examples. In particular, a three-dimensionalmathematical model of a particular bone having a flared surface regionproximate its terminal end is created, using a three-dimensional scan ofeither an actual human bone or an artificial model of a human bone, or athree-dimensional model created entirely by computer. Computer aideddrafting software is then used in conjunction with thisthree-dimensional mathematical model of the bone to create a bone plateof the present invention having a back surface profile of angled region47, first region 48 and second region 46 such that, when the prongmembers are impacted proximate the terminal end of the bone, this backsurface profile substantially corresponds to the adjacent flared contourof the bone, such that the bone plate rests substantially adjacent thebone.

Referring to FIG. 2C, in a preferred embodiment of a six-hole hook plateof the present invention, wherein the instrument has an overall lengthof approximately 2.874 inches, and a length of elongated body 41 betweenfirst end 42 and second end 43 of approximately 2.278 inches, firstangle of curvature 52 has a radius of approximately 0.380 inches,yielding a first curved bend angle 69 of approximately 25° at thejunction of the bottom surface of angled region 47 and the bottomsurface of first region 48 of elongated body 41. Moreover, for thisembodiment of a six-hole hook plate of the present invention, secondangle of curvature 50 has a radius of approximately 0.500 inches,yielding a second curved bend angle 49 of approximately 10° at thejunction of the bottom surface of angled region 47 and the bottomsurface of second region 46 of elongated body 41. Although, in apreferred embodiment, these two bend angles are achieved throughcurvature of portions elongated body 41, sharper bends, rather than moregentle curves, may alternatively be used.

First hook member 44 includes curved region 58, having an apex 54 andcurving from first region 48 of elongated body 41, curving back upon thebottom surface of elongated body 41, back towards second end 43 andterminating in first pointed prong region 61. Similarly, second hookmember 45 includes curved region 53, having an apex 59 and curving fromfirst region 48 of elongated body 41, curving back upon the bottomsurface of elongated body 41, back towards second end 43 and terminatingin second pointed prong region 56. In a preferred embodiment of asix-hole hook plate of the present invention, wherein the instrument hasan overall length of approximately 2.874 inches, and a length ofelongated body 41 between first end 42 and second end 43 ofapproximately 2.278 inches, first prong region 61 and second prongregion 56 both have a length of approximately 0.390 inches, as measuredfrom apex to tip.

In the left offset plate, and as best seen in FIGS. 2B and 2D, hookplate 40 is not bilaterally symmetrical, relative to the longitudinalaxis of elongated body 41. In particular, curved region 58 and its apex54 of first hook member 44 is more distally spaced than curved region 53and its apex 59, relative to both first end 42 and second end 43 ofelongated body 41. In particular, in a preferred embodiment, apex 54 offirst hook member 44 extends approximately 2 millimeters farther thanapex 59 of second hook member 45, relative to second end 41 of elongatedbody 41. This asymmetrical configuration permits hook members 44 and 45,and hook plate 40 overall, to more closely approximate the oftenasymmetric contour of the distal surface of the fibula at the lateralmalleolus, upon securement of hook plate 40 across the fracture site. Inanother embodiment, the surgeon is provided with a selection of platesin which the apex 54 of first hook 44 extends the same distance as theapex of 59 of the second hook member 45 (i.e., a bilaterally symmetricalhook plate); as well as a plate in which the apex 59 of second hook 45extends 2 mm farther than the apex 54 of first hook 44 (i.e., a rightoffset plate). It can be seen by those skilled in the art that thesevariations can be values other than 2 mm and are intended to accommodatevariability of the surface anatomy at the site of application.

As best seen in FIG. 2E, hook plate 40 has an arcuate cross section andbottom surface, along substantially all of the length of elongated body41. This curved bottom surface permits hook plate 40 to more closelyapproximate the curved longitudinal surface of the fibula, uponsecurement of hook plate 40 across the fracture site.

Referring to FIG. 2C, prong region 56 of second hook member 45 has alongitudinal axis 55. Angled region 47 of elongated body 41 has alongitudinal axis 63. As shown in FIG. 2C, longitudinal axis 55 ofsecond hook member 45 is substantially parallel to longitudinal axis 63of angled region 47. Moreover, prong region 61 of first prong member 44likewise has a longitudinal axis that is substantially parallel tolongitudinal axis 63 of angled region 47. As explained in detail below,this parallel relationship is critical to allow hook plate 40 to seatcongruently against the curved profile of the lateral malleolus as thehook members are impacted into a terminal fragment.

While, the example embodiment of the present invention shown in FIGS. 2Athrough 2F is configured for use in conjunction with fractures of theleft fibula at the lateral malleolus, other configurations are alsocontemplated by the present invention. For example, FIGS. 3A and 3B showanother, ten-hole embodiment of the present invention, configured foruse in conjunction with fractures of the right lateral malleolus.Referring to FIGS. 3A and 3B, bone plate 70 is shown as comprisingelongated body 71, having a first end 72 proximate first hook member, ortooth member 74 and second hook member, or tooth member 75, and a secondend 75. Elongated body 71 includes a plurality of apertures therethroughfor use in conjunction with conventional bone screws, including ninecircular holes 78, and one slotted hole 79. First hook member 74includes a first curved region having an apex 76. Second hook member 75includes a curved region having an apex 77.

While bone plate 70 likewise displays bilateral asymmetry relative toits longitudinal axis, it is second hook member 75 having apex 77, onthe right side of the bone plate, that is more distally spaced fromfirst end 72 and second end 73 of elongated body 71. By way of contrast,in the previously described embodiment, it is first hook member 44having apex 54, on the left side of the bone plate, that is moredistally spaced from first end 42 and second end 43 of elongated body41. This “mirror image” general configuration of bone plate 70, relativeto bone plate 40, permits bone plate 70 to more closely approximate thecurvilinear contoured distal surface of the right fibula at the lateralmalleolus, upon securement of hook plate 70 across a fracture site.

Although both a six-hole left bone plate and a ten-hole right bone platehave been described above, other configurations of the present inventionare also contemplated, including both left and right variations of boneplates, ranging in size from a four-hole bone plate, having an overalllength of approximately 2.264 inches, to a twelve-hole bone plate,having an overall length of approximately 5.335 inches, or longer plateswith more holes. Moreover, although, in preferred embodiments, each boneplate includes one slotted or oval hole for use in cooperation with bonescrews, with the remaining holes being circular, other combinations ofslotted and round bone screw accepting holes may alternatively be used.Alternatively, the hooks may be of identical length.

The present invention also comprises a double barreled drill guide,configured to direct a drill or K-wire in the proper depth and angle,relative to the lateral malleolus, such that, after pilot holes aredrilled for the hook members and upon subsequently impacting the hookmembers of the present hook plate, the bottom surface of the hook platetracks, and, when fully seated, is substantially adjacent, the surfacecontour of the lateral malleolus and the adjacent lateral surface of thefibula. The double barreled drill guide of the present invention isshown in FIGS. 4 and 5 as comprising drill guide base assembly 100. Inaddition, this guide may also be used with an interchangeable drillguide insert 140.

Drill guide base assembly 100 is shown in FIGS. 5 through 7C ascomprising body portion 111, two base sleeves 120, and base positioningmember 130. Body portion 111 has two apertures 114 extendingtherethrough, and two arm members 113, each having an associatedaperture 112 extending therethrough. As shown in FIG. 7C, apertures 112and 114 are canted slightly towards each other by a predetermined angle115, relative to their respective longitudinal axes. In a preferredembodiment, predetermined angle 115 is a slight, acute approximately 3degrees. This slight angle accounts for a certain amount of relativeflex in the components of the drill guide and results in a substantiallyparallel alignment of the sleeves and the base positioning member uponapplication of the base positioning member against a superficial surfaceof the terminal end of the bone. In an alternative embodiment of thepresent invention, no predetermined angle 115 is employed, as thesleeves and base positioning member have longitudinal axes that aresubstantially parallel to each other. Upon assembly of drill guide baseassembly 100, this, in turn, places each of base sleeves 120 atpredetermined angle 115, canted towards base positioning member 130.This likewise places the sleeves of interchangeable drill guide insert140 at predetermined angle 115, canted towards base positioning member130, upon insertion of the drill guide insert 140 into base assembly100. As a result, the two pilot holes for the hook members of thepresent invention are drilled at predetermined angle 115, relative tobase positioning member 130. Body portion 113 is preferably constructedof a surgical stainless steel material, such as type 303 surgicalstainless steel.

Base sleeve 120 is shown in FIG. 6 as comprising a generally tubularbody having a first end 121, shoulder 122, collar region 123, and secondend. First end 121 has a chamfered and serrated configuration,permitting drill guide base assembly 100 to grip the distal surface ofthe lateral malleolus when positioned prior to drilling pilot holes forthe hook members of the bone plate as shown in FIG. 4, serving toinhibit unwanted slippage of the overall drill guide. An internalchannel communicates between openings at first end 121 and second end122, and is sized to axially receive a drill. In a preferred embodiment,collar region 123 has a length of approximately 0.400 inches, and basesleeve 120 has an overall length of approximately 1.025 inches. Basesleeve 120 is preferably constructed of a surgical stainless steelmaterial, such as type 455 surgical stainless steel, condition H-900.

As shown in FIG. 6, base positioning member 130 is substantiallyU-shaped, having two elongated arms 131 and U-shaped end 132. Basepositioning member 130 is preferably constructed of a stainless steelmaterial, such as type 316LS stainless steel having a minimum ultimatetensile strength of 160 KSI. In another embodiment, base positioningmember 130 may be of the form of a plate having a contoured surfaceapproximating the contoured elongated body of the bone plate to beimplanted, or one or more pins (not shown).

Drill guide base assembly 100 is assembled by press fitting each basesleeve 120 though an associated aperture 112 of arm 113 of body portion111, until shoulder 122 rests adjacent a top surface of arm 113. Basepositioning member 130 is affixed to body portion 111 by inserting eachelongated arm 131 through an associated aperture 114 of body portion111, and then welding base positioning member in place using a nickel orother suitable braze.

Interchangeable drill guide insert 140 is shown in FIGS. 8A and 8B ascomprising generally T-shaped body 150 and two tubular insert sleeves160. T-shaped body 150 includes two apertures 151 extendingtherethrough, each accepting an associated insert sleeve 160, which isassembled by press-fitting each inner sleeve 160 into an associatedaperture 151. Two inwardly curving recesses extending along T-shapedbody 150 have a radius of curvature coinciding with the exterior surfaceof collar region 123 of base sleeve 120 of drill guide base assembly100, serving to further secure interchangeable drill guide insert 140 todrill guide base assembly 100, as tubular insert sleeves 160 areadvanced within associated base sleeves 120 until T-shaped body 150 isfully seated adjacent body portion 111 of drill guide base assembly 100.T-shaped body 150 is preferably constructed of a surgical stainlesssteel material, such as type 303 surgical stainless steel.

Each insert sleeve 160 includes a tapered first end 161, second end 162,and an internal channel communicating between openings at first end 161and second end 162. This internal channel is sized to accommodate aguide wire of a predetermined size, such as a 0.9 millimeter Kirshnerwire, or K-wire, to be used in conjunction with a 2.0 mm cannulateddrill that is subsequently guided over the wire upon removal of thedouble barreled drill guide, creating the pilot holes to accept axialimpacting of the hook members of the present bone plate. This, in turn,gives the surgeon the option of either drilling holes directly into theterminal bone fragment using a non-cannulated drill by using guideassembly 100 without the insert 140, or, if less speed and greaterpotential precision is desired, to first insert a K-wire, and then passa cannulated drill over the wire by using guide assembly 100 with insert140. In a preferred embodiment of the present invention, insert sleeve150 is approximately 1.150 inches in length. Insert sleeve 160 ispreferably constructed of a surgical stainless steel material, such astype 455 surgical stainless steel, condition H-900.

As shown in FIG. 8A, T-shaped body 150 includes laser-etched indicia152, indicating the size of guide wire accommodated by the presentinterchangeable drill guide insert 140, in this case a 0.9 millimeterguide wire. Moreover, as other interchangeable drill and guide wireinserts of varying sizes may alternatively be used, laser-etched indicia152 is changed as necessary indicate the particular drill or guide wiresize for each variation of interchangeable drill guide insert 140.

In addition to releasably accepting interchangeable drill guide insert140, drill guide base assembly 100 also releasably accepts a reversiblegauge assembly 170, shown in FIGS. 9A through 9C as comprising T-shapedgauge body 180, first cylindrical elongated member, or trocar 190 havingtapered end 191, and second cylindrical elongated member, or trocar 200having tapered end 201. T-shaped body 180 includes two apertures 181extending therethrough, each accepting an associated cylindrical trocar,and is assembled by press-fitting the trocars into associated apertures.Two inwardly curving recesses extending along T-shaped body 180 have aradius of curvature coinciding with the exterior surface of collarregion 123 of base sleeve 120 of drill guide base assembly 100, servingto further secure gauge assembly 170 to drill guide base member 100, ascylindrical trocars 190 and 200 are advanced within associated basesleeves 120 until T-shaped body 180 is fully seated adjacent bodyportion 111 of drill guide base member 100. T-shaped body 180 furtherincludes laser etched indicia 183 and 184, indicating “LEFT” and“RIGHT”, respectively, on opposing sides of the T-shaped body. T-shapedbody 180 is preferably constructed of a surgical stainless steelmaterial, such as type 303 surgical stainless steel.

As shown in FIGS. 9A through 9C, first trocar 190 and second 200 are ofdifferent lengths, with first trocar 190 being longer than trocar 200.In a preferred embodiment, first trocar 190 is approximately 2 mm longerthan second trocar 200, with first trocar being approximately 1.273inches in length, and second trocar being approximately 1.150 inches inlength. This differential permits a surgeon, prior to drilling any pilotholes, to use reversible gauge assembly 170 to confirm appropriate useof either a left or right offset hook plate of the present invention toproperly accommodate the inclination of the bone curvature at the entrysites for the hooks and permit the hook plate to be properly seatedadjacent the fibula upon impacting the hook members. In particular, oncethe double barreled drill guide is positioned adjacent the lateralmalleolus as shown in FIG. 4, gauge assembly 170 is inserted into drillguide base assembly 100. Upon insertion, if the indicia 183 or 184facing laterally, or outwardly is a correct indication of the leftversus right offset hook plate to be used, the differential in lengthsof trocars 190 and 200 will approximate the curvature of the lateralmalleolus at the distal end of the fibula, and gauge assembly 170 willbe substantially fully seated within base assembly 100. If, however,gauge assembly 170 does not substantially fully seat within baseassembly 100, this is a visual indication that, since the differentialin length of the trocars does not follow the contoured distal surface ofthe lateral malleolus, the indicia facing outwardly or laterally is mostlikely incorrect. In this case, the gauge assembly 170 can be withdrawnand flipped, and then reinserted to determine if the opposite offsethook plate is required. If the gauge assembly fully seats, it isindicative of the proper offset plate to use. If the gauge assembly doesnot seat when inserted with either attitude, it is indicative that azero offset, bilaterally symmetrical plate is required.

As shown in FIG. 10, once the pilot holes are drilled using the doublebarreled drill guide (or once K-wires are positioned using the drillguide, and a cannulated drill is advanced over the wire to prepare thepilot holes), hook members 44 and 45 of hook plate 40 are longitudinallyadvanced into the pilot holes along longitudinal axis 55 of the hookmembers, using a hammer or other suitable instrument. Since the drillguide references the proper entry site and trajectory of the drillholes, impaction of the plate 40 into bone causes the plate to advancealong longitudinal axis 63. When fully seated, first region 46, secondregion 48, and intermediate angled region 47 come to lie congruentlyalong the curved surface of the bone. This anatomic fit of the plateagainst the bone is the result of designing the longitudinal axis 55 ofthe hooks to be parallel to the longitudinal axis 63 of the intermediateregion 47, and to the creation of the specific entry site in the boneusing the double barreled guide assembly 70 that matches the depth andtrajectory of hooks 44 and 45. Following full axial insertion of thehook members, this, in turn, causes elongated body 41 of hook plate 40to come to rest substantially adjacent the distal end of the fibula,with longitudinal axis 63 of angled region 47 substantially parallel toand coinciding with the flared end of the fibula at the lateralmalleolus, as shown in FIGS. 11 and 12. Bone screws are then placedthrough appropriate circular and slotted holes of hook plate 40 and intothe fibula, as desired, to secure hook plate 40 in place.

Although, as described above, a drill is used to prepare pilot holes inthe lateral malleolus to receive the hook members, for patients withrelatively soft bone, a surgeon may potentially opt to forego thepreparation of pilot holes, and axially hammer the hook members of thebone plate of the present invention directly into place. Moreover,although the embodiment of the present invention discussed above isdesigned for use in conjunction with fractures of the lateral malleolusof the fibula, it may also be used in the configuration discussed abovein conjunction with fractures of the medial malleolus of the tibia orother sites as discussed previously. Moreover, the overall lengths ofthe angled region, first region and second region of the elongated body,as well as the relative angles of the angled region with respect to theadjacent first and second regions of the elongated body, may be modifiedto more closely accommodate the terminal ends of other bones, such asthe medial malleolus of the tibia, for the treatment of fracturesthereof.

A simplified medial view of a portion of a fractured right human distalradius 210 is shown in FIG. 19 as comprising distal radial epiphysis 211including volar rim 212 and dorsal rim 213, and distal radial metaphysis214. For illustrative purposes, distal radius 210 is shown having aplurality of fragments 215 associated with a fracture site.

A four-hole, neutral offset bone plate 220 of the present invention,configured for volar application in conjunction with fractures of distalradius, is shown in FIGS. 13A through 13E as comprising an elongatedbody 221, having a first end 222 proximate first hook member, or toothmember 224 and second hook member, or tooth member 225. Elongated body221 includes a first region 228 proximate first end 222, a second region226 proximate a second end 223, and an intermediate, angled, or “flared”region 227 disposed between first region 228 and second region 226.Elongated body 221 includes a plurality of apertures extendingtherethrough for use in conjunction with conventional locking ornon-locking bone screws, including three circular holes 235, and oneslotted hole 236. As best seen in FIGS. 13D and 13E, circular holes 235and slotted hole 236 are substantially collinear in orientation.Alternatively, circular holes 235 may collectively have a staggeredoff-center orientation, relative to a longitudinal axis of elongatedbody 221, while slotted hole 236 may remain centered along thislongitudinal axis. Moreover, and as best seen in FIG. 13A, slotted hole236 and each circular hole 235 includes an associated countersunk,beveled perimeter, relative to the top surface of elongated body 221,facilitating the frusto-conical heads of conventional bone screws to befully seated against, and hence in securing engagement with, anassociated hole upon implantation. The countersunk, beveled perimeter ofthese apertures further serve to direct each associated bone screw intoa desired orientation, typically substantially perpendicular to theadjacent portion of the contoured surface of elongated body 221.

As best seen in FIG. 13C, angled region 227 is generally defined andcreated by the presence of an angle of curvature 229 relative to thebottom surface of bone plate 220 proximate the juncture of substantiallylinear first region 228 and substantially linear angled, or flaredregion 227. The length of the linear angled region 227 and theinclination defined by the angle of curvature 229 substantially matchthe length and inclination of the flare of the associated bone requiringfracture fixation, in this case the radius, with volar applicationproximate the volar rim at the distal radial epiphyseal plate. It shouldbe noted that substantially linear first region 228 may alternatively bea curved surface that may be approximated by a best fit inclinationangle. As a result, the bottom surface of elongated body 221 of boneplate 220 is given an overall longitudinal contour which substantiallycorresponds to the flared profile of the distal end of the human radiusproximate the volar rim.

In one preferred embodiment, the length, contour and relative angling oflinear angled region 227, relative to first region 228 and second region226, is designed to match the flare of the surface contour of the siteof application using an electronically scanned or mathematicalthree-dimensional model of the site of application, such as the dorsalrim, volar rim, or radial arm of the distal radius as examples. Inparticular, a three-dimensional mathematical model of a particular bonehaving a flared surface region proximate its terminal end is created,using a three-dimensional scan of either an actual human bone or anartificial model of a human bone, or a three-dimensional model createdentirely by computer. Computer aided drafting software is then used inconjunction with this three-dimensional mathematical model of the boneto create a bone plate of the present invention having a back surfaceprofile of angled region 227, first region 228 and second region 226such that, when the prong members are impacted proximate the terminalend of the bone, this back surface profile substantially corresponds tothe adjacent flared contour of the bone, such that the bone plate restssubstantially adjacent the bone.

Referring to FIG. 13C, in a preferred embodiment of a four-hole neutralvolar hook plate of the present invention, flare angle 229 isapproximately 25° in curvature. Moreover, first toothed member 224 andsecond toothed member 225 are each disposed at an angle 231, relative toa longitudinal axis of flared region 227, at an angle of approximately50°. Although, in a preferred embodiment, these two bend angles areachieved through curvature of portions of hook plate 220, sharper bends,rather than more gentle curves, may alternatively be used.

Bone plate 220 is shown in FIGS. 20 and 21 during implantation, impactedvolarly into distal radius 210 adjacent volar rim 212 and prior to theplacement of bone screws through holes 235 and 236. Next, as shown inFIG. 23, bone screws 500 are placed through one or more of holes 235 and236 to secure bone plate 220 to the distal radius. For further enhancedsecurement, distal locking peg 219 is placed through a forward-most hole217 which, in conjunction with countersunk aperture 218, directs distallocking peg to be positioned between first toothed member 224 and secondtoothed member 225.

A four-hole, left offset bone plate 240 of the present invention,configured for volar application in conjunction with fractures of distalradius, is shown in FIGS. 14A through 14D as comprising an elongatedbody having a first end 243 proximate first hook member, or tooth member241 and second hook member, or tooth member 242, and a second end 244.In the left offset version, hook plate 240 is generally similar inconfiguration to hook plate 220, but is not bilaterally symmetrical,relative to the longitudinal central axis 245 of hook plate 240. Inparticular, as best seen in FIGS. 14C and 14D, a central vertical axis246 of hook member 241 has a horizontal spacing 248 from longitudinalcentral axis 245 that is approximately twice that of horizontal spacing249 of central vertical axis 247 from longitudinal central axis 245 ofhook plate 240, yielding a larger left offset region 250. Thisasymmetrical configuration permits the selective use of left offset hookplate 240 in situations where use of neutral hook plate 220 wouldotherwise place a hook member through an undesired location of thedistal radial fracture, such as at the juncture of a fragment, ratherthan through a fragment itself. It can be seen by those skilled in theart that variations in the left offset of the hook member other thantwice the distance of the right hook member from the centrallongitudinal axis of the hook plate may alternatively be used.

A four-hole, right offset bone plate 260 of the present invention,configured for volar application in conjunction with fractures of distalradius, is shown in FIGS. 15A through 15D as comprising an elongatedbody having a first end 263 proximate first hook member, or tooth member261 and second hook member, or tooth member 262, and a second end 264.In the right offset version, hook plate 260 is generally similar inconfiguration to hook plate 220, but is not bilaterally symmetrical,relative to the longitudinal central axis 265 of hook plate 260. Inparticular, as best seen in FIGS. 15C and 15D, a central vertical axis267 of hook member 262 has a horizontal spacing 269 from longitudinalcentral axis 265 that is approximately twice that of horizontal spacing268 of central vertical axis 266 from longitudinal central axis 265 ofhook plate 260, yielding a larger right offset region 270. Thisasymmetrical configuration permits the selective use of right offsethook plate 240 in situations where use of neutral hook plate 220 or leftoffset hook plate 240 would otherwise place a hook member through anundesired location of the distal radial fracture, such as at thejuncture of a fragment, rather than through a fragment itself. It can beseen by those skilled in the art that variations in the right offset ofthe hook member other than twice the distance of the right hook memberfrom the central longitudinal axis of the hook plate may alternativelybe used.

Left and right offset bone plates 240 and 260, respectively are shown inFIG. 22 during simultaneous implantation, impacted volarly into distalradius 210 in substantially parallel orientation adjacent volar rim 212and prior to the placement of bone screws through holes 235 and 236.When so implanted, as shown in FIG. 22, left offset region 250 of boneplate 240 and right offset region 270 of bone plate 260 are disposed atopposing ends of volar rim 212.

A seven-hole, neutral offset bone plate 280 of the present invention,configured for volar application in conjunction with fractures of distalradius, is shown in FIGS. 16A through 16C as comprising an elongatedbody 281, having a first end 282 proximate first hook member, or toothmember 284 and second hook member, or tooth member 285. Elongated body281 includes a first region proximate first end 282, a second regionproximate a second end 283, and an intermediate, angled, or “flared”region disposed between the first region and the second region.Elongated body 281 further includes a plurality of apertures extendingtherethrough for use in conjunction with conventional locking ornon-locking bone screws, including six circular holes 295, and oneslotted hole 296. Circular holes 295 and slotted hole 296 aresubstantially collinear in orientation. Alternatively, circular holes295 may be collectively have a staggered off-center orientation,relative to a longitudinal axis of elongated body 281, while slottedhole 296 may remain centered along this longitudinal axis. Moreover, andas best seen in FIG. 16A, slotted hole 296 and each circular hole 295includes an associated countersunk, beveled perimeter, relative to thetop surface of elongated body 281, facilitating the frusto-conical headsof conventional bone screws to be fully seated against, and hence insecuring engagement with, an associated hole upon implantation. Thecountersunk, beveled perimeter of these apertures further serve todirect each associated bone screw into a desired orientation, typicallysubstantially perpendicular to the adjacent portion of the contouredsurface of elongated body 281.

As best seen in FIG. 16C, angled, or flared region 287 proximate prongregion 293 is generally defined and created by the presence of an angleof curvature 289 relative to the bottom surface of bone plate 280proximate the juncture of substantially linear first region 288 andsubstantially linear angled, or flared region 287. The length of thelinear angled region 287 and the inclination defined by the angle ofcurvature 289 substantially match the length and inclination of theflare of the associated bone requiring fracture fixation, in this casethe radius, with volar application proximate the volar rim at the distalradial epiphyseal plate. It should be noted that substantially linearfirst region 288 or second region 287 may alternatively be a curvedsurface that may be approximated by a best fit inclination angle. As aresult, the bottom surface of elongated body 286 of bone plate 280 isgiven an overall longitudinal contour which substantially corresponds tothe flared profile of the distal end of the human radius proximate thevolar rim.

Referring to FIG. 16C, in a preferred embodiment of a seven-hole neutralvolar hook plate of the present invention, flare angle 289 isapproximately 25° in curvature. Moreover, first toothed member 284 andsecond toothed member 285 are each disposed at an angle 295, relative toa longitudinal axis of flared region 287, at an angle of approximately50°. Although, in a preferred embodiment, these two bend angles areachieved through curvature of portions of hook plate 280, sharper bends,rather than more gentle curves, may alternatively be used.

A four-hole, neutral offset bone plate 300 of the present invention,configured for dorsal application in conjunction with fractures ofdistal radius, is shown in FIGS. 17A through 17E as comprising anelongated body 301, having a first end 302 proximate first hook member,or tooth member 304 and second hook member, or tooth member 305.Elongated body 301 includes a curved apex 311 proximate first end 302, asecond region 306 proximate a second end 303, and an intermediate,angled, or “flared” region 307 disposed between curved apex 311 andsecond region 306. Elongated body 301 includes a plurality of aperturesextending therethrough for use in conjunction with conventional lockingor non-locking bone screws, including three circular holes 315, and oneslotted hole 316. As best seen in FIGS. 17D and 17E, circular holes 315and slotted hole 316 are substantially collinear in orientation.Alternatively, circular holes 316 may collectively have a staggeredoff-center orientation, relative to a longitudinal axis of elongatedbody 301, while slotted hole 316 may remain centered along thislongitudinal axis. Moreover, and as best seen in FIG. 17A, slotted hole316 and each circular hole 315 includes an associated countersunk,beveled perimeter, relative to the top surface of elongated body 301,facilitating the frusto-conical heads of conventional bone screws to befully seated against, and hence in securing engagement with, anassociated hole upon implantation. The countersunk, beveled perimeter ofthese apertures further serve to direct each associated bone screw intoa desired orientation, typically substantially perpendicular to theadjacent portion of the contoured surface of elongated body 301.

As best seen in FIG. 17C, angled or flared region 307 is generallydefined and created by the presence of an angle of curvature 309relative to the bottom surface of bone plate 300 proximate the junctureof substantially linear first region 301 and substantially linearangled, or flared region 307. The length of the linear angled region 307and the inclination defined by the angle of curvature 309 substantiallymatch the length and inclination of the flare of the associated bonerequiring fracture fixation, in this case the radius, with dorsalapplication proximate the dorsal rim at the distal radial epiphysealplate. It should be noted that substantially linear first region 307 mayalternatively be a curved surface that may be approximated by a best fitinclination angle. As a result, the bottom surface of elongated body 301of bone plate 300 is given an overall longitudinal contour whichsubstantially corresponds to the flared profile of the distal end of thehuman radius proximate the dorsal rim.

Referring to FIG. 17C, in a preferred embodiment of a four-hole neutraldorsal hook plate of the present invention, flare angle 309 isapproximately 175° in curvature. Alternatively, this region may bestraight with a flare angle 309 of 180°. Moreover, first toothed member304 and second toothed member 305 are each disposed at an angle 314,relative to a longitudinal axis of flared region 307, at an angle ofapproximately 75°. Although, in a preferred embodiment, these two bendangles are achieved through curvature of portions of hook plate 300,sharper bends, rather than more gentle curves, may alternatively beused.

A longer, seven-hole neutral dorsal radial bone plate 450, generallysimilar in overall configuration to four-hole hook plate 300 describedabove, is shown in FIGS. 24A and 24B during implantation, impacteddorsally into distal radius 210 adjacent dorsal rim 213 and prior to theplacement of bone screws through holes 455 and 456. As best seen in FIG.24B, flare angle 459 closely accommodates the slightly curved surface ofdistal radius 210 adjacent dorsal rim 213, and both first toothed member454 and second toothed member 455, at second end 452 of hook plate 450,are impacted into the cortical bone region of the distal radius, in adirection generally transverse to a longitudinal axis of the distalradius, proximate the metaphyseal region. It should be noted that firsttoothed member 454 and second toothed member 455 provide support behindthe dorsal sub-articular bone.

A three, five or seven-hole, neutral offset bone plate 320 of thepresent invention, configured for radial arm application in conjunctionwith fractures of distal radius, is shown in FIG. 18 followingimplantation and reduction of such a fracture, as comprising anelongated body 321, having a first end 322 proximate first hook member,or toothed member 324 and a second hook member, or toothed member.Elongated body 321 includes a first region 328 proximate first end 322,a second region 326 proximate a second end 323, and an intermediate,angled, or “flared” region 327 disposed between first region 328 andsecond region 326. Elongated body 321 includes a plurality of aperturesextending therethrough for use in conjunction with conventional bonescrews 500. These may comprise a combination of circular and slottedholes, which may be substantially collinear in orientation, or which maycollectively have a staggered off-center orientation, relative to alongitudinal axis of elongated body 321. Moreover, each slotted andcircular hole includes an associated countersunk, beveled perimeter,relative to the top surface of elongated body 321, facilitating thefrusto-conical heads of conventional bone screws to be fully seatedagainst, and hence in securing engagement with, an associated hole uponimplantation. The countersunk, beveled perimeters of these aperturesfurther serve to direct each associated bone screw into a desiredorientation, relative to the adjacent portion of the contoured surfaceof elongated body 321.

As shown in FIG. 18, elongated body 321 includes holes 338 and 339, eachaccommodating an associated distal locking peg 219. Each distal lockingpeg 219 extends through the gap between the first and second toothedmembers of hook plate 320.

Moreover, as shown in FIG. 18, hook plate 320 may be constructed ofvarious lengths, such as, for example, a 3-hole hook plate terminatingat second end 335; a 5-hole hook plate terminating at second end 336; ora 7-hole hook plate terminating a second end 337. In the example of a7-hole hook plate, to accommodate the curvilinear surface of the radialarm of the distal radius, a second flare angle 325 is added to elongatedbody 326 of hook plate 320. In a preferred embodiment, second flareangle 325 may be approximately 160° in curvature.

For all of the above-described variations of hook plates of the presentinvention contoured for application to fractures of the distal radius,the first and second toothed members, which are substantially triangularin cross-section, are each preferably sharpened at the tip and along atleast one of the vertical edges to create sharp cutting surfaces. This,in turn, permits each of these hook plates to be impacted at thefracture site without the need to pre-drill pilot holes to accept thetoothed members, or tines of the hook plates. Instead, a holder/impactormay be used to securely hold the hook plate as it is first placed intoan appropriate position adjacent the fracture, and then impacted intoplace by driving the hook members through the epiphyseal region of thedistal radius. The use of a holder/impactor increases the simplicity ofengaging the hooks into bone and the precision of accurate placement ofthe plate by the surgeon.

The present invention also comprises a combination holding andcompacting instrument capable of both gripping a distal radius hookplate, and facilitating the impacting of the implant into distal bonefragments at the fracture site, without the need to pre-drill any pilotholes for the toothed members of the hook plate. In preferredembodiments, this instrument is attachable to and securely holds thehook plate proximate the first end, at the U-shaped juncture of thefirst and second toothed members, or times. Moreover, this instrumentmay preferably include a striking surface for receiving taps or blowsfrom a surgical mallet or hammer, permitting a bone plate held by theinstrument and suitably positioned to be directly impacted into thedistal bone fragments. Moreover, although, in preferred embodiments, acombination holding and impacting instruments are disclosed, the holdingand impacting of the hook plates of the present invention mayalternatively be accomplished through the use of a first dedicatedgripping instrument and a second dedicated impacting instrument.

A holder/impactor 400 for gripping and impacting the volar, dorsal, andradial arm distal radius hook plates of the present invention is shownin FIGS. 25 through 30 as comprising head member 401, having strikingsurface 402 and flanged region 403. Rigid elongated rod 405 couples headmember 401, at one end, to distal housing 407, at an opposing end of rod405. As best seen in FIGS. 27 and 30, distal housing 407 includes acontoured bottom surface 408, having a curvilinear form shaped toapproximate the top surface of a distal radial hook plate of the presentinvention, such as 7-hole neutral volar hook plate 280, adjacent the topsurface of the hook plate and proximate first end 282, proximate thesubstantially U-shaped junction of first tooth member 284 and secondtooth member 285. Distal housing 407 further includes top aperture 410,permitting the axial movement of a portion of sliding shaft 415therethrough, and shaped to accommodate the cross-section of slidingshaft 415, including guide rail 419, which is disposed longitudinally onone side of sliding shaft 415. Distal housing 407 also includes bottomslot 410, permitting the axial movement of foot member 47 andcylindrical riser 418 of sliding shaft 415 therethrough.

Sliding shaft 415 further includes tongue 416, which is disposedlongitudinally on an opposing side of shaft 415, relative to guide rail419, and runs along substantially the entire length of sliding shaft415. Tongue 416 is inserted within and slidably engages groove 420 ofelongated rod 405, which runs along substantially the entire length ofrod 405.

Adjuster 402 adjusts the vertical position of sliding shaft 415 alongand adjacent to elongated rod 405 and distal housing 407, and comprisesadjustment knob 421 and adjustment shaft 422, having threaded topportion 423 and bottom portion 424, which is rigidly affixed to slidingshaft 415. Adjustment knob 421 threadedly engages adjustment shaft 422and is positioned adjacent flanged region 403 of head member 401.Adjustment shaft 422 extends through an associated aperture 404 offlanged region 401. Bottom portion 424 of adjustment shaft 422 adjoinssliding shaft 415, and screws or other fastening means may be employedto affix adjustment shaft 422 of adjuster 402 to sliding shaft 415.Accordingly, as adjustment knob 421 is rotated in a first direction, itsthreaded engagement with threaded top portion 423 of shaft 422 impartsaxial downward movement of shaft 422, in the direction towards distalhousing 407. This, in turn, pushes sliding shaft 415 downward, causingfoot member 417 and cylindrical riser 418 at the distal end of slidingshaft 415 to be extended through bottom aperture 410 of distal housing407. Likewise, as adjustment knob 421 is rotated in a second, opposingdirection, its threaded engagement with threaded top portion 423 ofshaft 422 imparts axial upwards movement of shaft 422, in the directionaway from distal housing 407. This, in turn, pulls sliding shaft 415back upwards, causing foot member 417 and cylindrical riser 418 at thedistal end of sliding shaft 415 to be retracted back through bottomaperture 410 of distal housing 407.

As shown in FIGS. 25, 26, 28, 29 and 30, this back-and forth rotation ofknob 421 permits hook plate 280 to be securely gripped byholder/impactor 400. First, knob 421 is rotated in the first directionto extend foot member 417 and cylindrical riser 418 from distal housing407. Next, holder/impactor 400 is fitted to hook plate 280, by placingcontoured bottom surface 408 of distal housing 407 adjacent the topsurface of hook plate 280 at first end 282. At the same time, footmember 417 is placed adjacent the bottom surface of hook plate 280 atfirst end 282, with cylindrical riser 418 nestled adjacent the U-shapedregion between first toothed member 284 and second toothed member 285.Knob 421 is then rotated in the second direction, retracting food member417 and cylindrical riser 418 towards distal housing 407. This, in turn,causes hook plate 280 to be securely gripped by holder/impactor 400,with first end 282 of hook plate 280 sandwiched between foot member 417on the bottom and contoured bottom surface 408 of distal housing 407 ontop, and with the abutment of cylindrical riser 418 and the U-shapedregion between the toothed members of hook plate 420 further serving totightly retain hook member 420 in place.

Next, hook plate 420 is positioned volarly, proximate a fracture of thevolar rim of the distal radius. For other varieties of the distal radiushook plates of the present invention, the hook plate may be placeddorsally, or alongside the radial arm of the distal radius. A suitablesurgical mallet or hammer is then employed to repeatedly tap or hitstriking surface 402 of head member 401 to, in turn, drive toothedmembers 284 and 285 of hook plate 280 into the distal radius, includinginto distal bone fragments at the fracture site. Notably, uponattachment to a hook plate, elongated rod 405 is substantially collinearwith the longitudinal axes of the toothed members of the hook plate.Accordingly, the force of taps or blows given to striking surface 402are directed through elongated rod 405 and distal housing 407 to, inturn, provide an impacting force at the fracture site substantiallyalong the longitudinal axes of the toothed members being impacted intothe distal fragments. Hook plate 280 is preferably impacted most, butnot all of the way in place in this manner, leaving enough room beneaththe bottom surface of hook plate 280 for foot member 401 to be slightlyextended away from distal housing 407 through the rotation of adjustmentknob 401 in the first direction to, in turn, loosen the grip ofholder/impactor 400 on hook member 280. Holder/impactor 400 is thenremoved, by drawing foot member 417 forward and away from hook plate280, between toothed members 284 and 285. The surgical hammer or mallet,usually with a simple surface impactor, may then be employed to directlystrike hook member 280, such as proximate first end 282, in order tocomplete the impaction of the hook plate. Suitable surgical screws anddistal locking pegs may then be employed to fully reduce the fracture,and to secure hook plate 280 in place adjacent the distal radius at thefracture site.

Another embodiment of a holder/impactor 430 of the present invention isshown in FIGS. 31 and 32 as comprising head member 431 having strikingsurface 440, distal gripping region 433, and elongated shaft 432connecting head member 431 and distal gripping region 433. Distalgripping region 433 includes bottom surface 434 that is contoured toapproximate the contoured top surface of hook plate 220 to be implanted,proximate first end 222 of hook plate 220. Distal gripping regionfurther includes a transverse slot 435, surrounded on both top andbottom surfaces by overhanging flanges 438, and threaded hole 436disposed through the top overhanging flange 438. Locking thumbscrew 437has a threaded distal region that threadedly engages female threadsdisposed within threaded hole 436 of distal gripping region 433.

To attach holder/impactor 430 to hook plate 220, a portion of distalgripping 433 region is inserted into the U-shaped region between thefirst and second toothed members at first end 222 of hook plate 220,with each tooth member overhanging region 439 overlying an associatedtoothed member. In this position, a portion of first end 222 of hookplate 220 is disposed within transverse slot 435, and is partiallysandwiched between both top and bottom surfaces by overhanging flanges438. Locking thumbscrew 437 is then tightened, such that a distal tip ofthumbscrew 437 extends through the bottom surface of distal grippingregion 433 and engages the top surface of hook plate 220, therebybiasing tooth member overhang regions 439 against corresponding top endsof associated toothed members, securing holder/impactor 430 to hookmember 220.

A suitable surgical mallet or hammer is then employed to repeatedly tapor hit striking surface 440 of head member 431 to, in turn, drive thetoothed members of hook plate 220 into the distal radius. Notably, uponattachment to a hook plate, elongated shaft 432 is substantiallycollinear with the longitudinal axes of the toothed members of the hookplate. Accordingly, the force of taps or blows given to striking 440 aredirected through shaft 432 and distal gripping region 433 to, in turn,provide an impacting force at the fracture site substantially along thelongitudinal axes of the toothed members being impacted into the distalfragments. Hook plate 220 is preferably impacted most, but not all ofthe way in place in this manner, leaving enough room beneath the bottomsurface of hook plate 220 for bottom overhanging flange 438 to be slidaway from underneath hook plate 220. Holder/impactor 430 is thenremoved, by first loosening thumbscrew 437, and the drawing distalgripping region 433 forward and away from hook plate 220, between thetoothed members. The surgical hammer or mallet, typically with a simplesurface impactor, may then be employed to directly strike hook member220, such as proximate first end 222, in order to complete the impactionof the hook plate. Suitable surgical screws and distal locking pegs maythen be employed to fully reduce the fracture, and to secure hook plate220 in place adjacent the distal radius at the fracture site.

In preferred embodiments, the hook plates of the present invention maybe constructed of wrought 18chromium-14nickel-2.5 molybdenum stainlesssteel, having a tensile strength of at least 135 Kips per square inch(KSI), and meeting the chemical and mechanical properties established bythe ASTM-F139 standard. Other materials such as titanium, titaniumalloy, or medical grade polymers may alternatively be used.

The present invention also comprises kits of combinations of thecomponents described above. For example, a plurality of hook plates ofmultiple sizes, from four-hole to fifteen-hole embodiments in both leftand right offset variations, and possibly with zero offset variations,may be provided in kit form so that appropriately sized and configuredhook plates of the present invention are readily available at a hospitalor trauma center. Moreover, one or more hook plates may be provided inkit form in combination with the double barreled drill guide and/or theholder/impactor of the present invention. Furthermore, the doublebarreled drill guide and/or the holder/impactor, either alone or as apart of a kit of one or more hook plates, may themselves be provided asa kit or sub-kit including the base assembly, interchangeable drillguides sized to accommodate guide wires and/or non-cannulated drills ofvarying sizes, and the gauge assembly.

Although the present invention has discussed plates with two hooks, itwill be understood by those skilled in the art that other embodimentshaving one hook or a plurality of hooks are possible and do not departfrom the scope or spirit of the present invention.

Although the present invention has shown two possible forms of agripping and impacting instrument, it will be understood by thoseskilled in the art that these are provided as example and manyvariations of embodiments of instruments to rigidly grip and impact theplate are possible and do not depart from the scope or spirit of thepresent invention. For example, a gripping instrument, an impactinginstrument, and/or a combination gripping and impacting instrument, maybe configured to threadably engage a threaded hole of the bone plate,such as, for example, modifying the embodiment of FIGS. 31 and 32 toenlarge contoured bottom surface 434, such that locking thumbscrew 437is directed into the threaded hole immediately adjacent first end 222 ofbone plate 220. Moreover, the contoured bottom surface 434 ofholder/impactor may be widened to overhang the side edges of a boneplate to, in turn, securely grip the bone plate by a portion of the sideedges of the bone plate, proximate the toothed members. A snap-fitattachment may potentially be used. Alternatively, a forceps-liketensioner, integral with or operably coupled to the instrument, mayoperate as a “spreader”, engaging the opposing inner surfaces of thetoothed members at their U-shaped junction at first end 222 to, in turn,bias the overhanging side edges of the instrument against the side edgesof the bone plate.

The preceding description and drawings merely explain the invention andthe invention is not limited thereto, as those of ordinary skill in theart who have the present disclosure before them will be able to makechanges and variations thereto without departing from the scope of thepresent invention.

1. An impacting instrument securely attachable to at least a portion ofa bone plate, the bone plate having an elongated body having a firstend, a second end, a top surface, a bottom surface, and at least twohook members disposed proximate the first end, the at least two hookmembers each having a prong region having a longitudinal axis; theimpacting instrument transferring force applied to a striking surface ofthe impacting instrument to the bone plate proximate the least two hookmembers.
 2. The invention according to claim 1, wherein at least aportion of the impacting instrument has a surface contour matching atleast a portion of a surface contour of the bone plate.
 3. The inventionaccording to claim 1, wherein the impacting instrument engages at leasta portion of the top surface of the elongated body and at least aportion of the bottom surface of the elongated body.
 4. The inventionaccording to claim 1, wherein at least a portion of the impactinginstrument securely grips at least a portion of the bone plate byengaging two opposing side edges of the bone plate.
 5. The inventionaccording to claim 1, wherein at least a portion of the impactinginstrument threadably engages at least a portion of bone plate.
 6. Theinvention according to claim 1, wherein the force applied to thestriking surface is transferred substantially collinearly to thelongitudinal axes of the at least two hook members.
 7. The inventionaccording to claim 1, wherein the impacting instrument further includesan adjustment mechanism permitting adjustment of a gripping forceapplied to at least a portion of the bone plate by the impactinginstrument.
 8. The invention according to claim 1, wherein each of theat least two hook members is sharpened at a distal tip, permitting theat least two hook members to be impacted through a cortical bone regionof a bone fracture site without drilling a pilot hole into the corticalbone region.
 9. The invention according to claim 1, wherein each prongregion has at least one longitudinal edge extending along at least aportion thereof, and wherein each hook member is sharpened along atleast a portion of its at least one longitudinal edge, permitting eachhook member to be impacted through a cortical bone region of a bonefracture site without drilling a pilot hole into the cortical boneregion.
 10. The invention according to claim 1, wherein the bone plateis configured for fixing fractures having at least one small terminalfragment of the distal radius.